cellxgene-census

Query CELLxGENE Census expression data across tissues, diseases, and cell types.

21|1|Updated Mar 19, 2026
One-click install
npx skills add https://github.com/OwnLabAI/ownlab --skill cellxgene-census-ownlabai
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: cellxgene-census
Source: https://github.com/OwnLabAI/ownlab/tree/main/mart/skills/scientific-skills/cellxgene-census
Command: npx skills add https://github.com/OwnLabAI/ownlab --skill cellxgene-census-ownlabai

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes references (resource) components.

What problem does it solve?

Programmatic access to the CELLxGENE Census enables scalable querying of millions of single-cell observations across tissues, diseases, and cell types, facilitating reproducible analyses and cross-dataset comparisons.

Core Features & Use Cases

  • Large-scale querying across datasets with built-in metadata filters (obs, var) and dataset presence
  • AnnData/Scanpy integration workflows for downstream analysis and visualization
  • Out-of-core and scalable workflows using axis_query for chunked processing of expression data
  • Multi-dataset analysis including cross-tissue comparisons and model training with PyTorch

Quick Start

Open CELLxGENE Census and run a small in-memory query for B cells in lung, returning an AnnData object for downstream analysis.

Frequently Asked Questions about cellxgene-census

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I query single-cell expression data across multiple tissues and diseases?

Query single-cell expression data across tissues and diseases using programmatic access to the CELLxGENE Census. You can filter by cell metadata, tissue types, and disease states to retrieve scalable, reproducible subsets of data for cross-dataset analysis.

Can I use AnnData and Scanpy with CELLxGENE Census for downstream analysis?

Yes, AnnData and Scanpy integrate with CELLxGENE Census for downstream analysis. You can run an in-memory query for specific cell types and tissues, returning an AnnData object directly compatible with Scanpy workflows for visualization and processing.

What is the best way to process millions of single-cell observations without running out of memory?

Use out-of-core querying with axis_query to process millions of single-cell observations in chunks. This scalable workflow prevents memory exhaustion by enabling chunked processing of expression data directly from the CELLxGENE Census.

Does querying CELLxGENE Census require specifying a census version for reproducibility?

Yes, specifying a census_version is required for reproducibility when querying CELLxGENE Census. It ensures that your programmatic access to single-cell expression data returns consistent results across different runs and analysis environments.

How do I filter primary data when querying single-cell datasets from the Census?

Apply the is_primary_data filter along with tissue_general and feature_id filters when querying single-cell datasets. These metadata filters ensure you retrieve only primary, non-duplicated observations for your specific tissue and gene targets.

Can I train PyTorch models using multi-dataset single-cell expression data?

Yes, you can train PyTorch models using multi-dataset single-cell expression data. The CELLxGENE Census supports multi-dataset analysis, allowing you to query and integrate cross-tissue comparisons and expression data for model training.